Decelerator



Feb 11,19447- RHA-"Isernia 2,415,491

INVENTOR.

' Patented Feb. 1l, 1947 v UNITED' -STATE-s PATENT DECELERATOR l Robert H. Hieger, Detroit, Mich., assignor to George M. Holley and Earl Holley Application September 29, 1945, Serial No. 619,332

2 Claims.

iadjustable needle I56 controls a connection from the inlet manifold 58 to the passage 5t. Clean air-for the air entrance venturi 52 is provided by a passage 88.

Operation when the throttle ls is closed to the position l shown, a, high suction is developed in the mani- The drawing shows the preferred form of myv invention.

The air enters atvl and ows by the choke valve I2 and then by a fuel nozzle Hi, which discharges into the throat of the venturi I6. Air

then flows by a throttle I8, which controls an idling outlet 28 and a second low-speed outlet 22, both idling outlets being connected through the low-speed fuel passage 24, which is connected to the idling fuel passage 26, which draws fuel from the fuel nozzle I4. The nozzle I8 is supplied with fuel from the main fuel-supply passage 28, which is in restricted communication with the float chamber 38, 32 is a vvalve which serves, when moved to the left, to block the passage 26 from the passage 2t. The chamber 38, to the right of the diaphragm 36, is in communication through a passage in the valve 32 and through the im- 1 pact tube 92 with the air entering the carburetor at i8. The diaphragm 36 forms the left-hand wall of chamber 3d and the right-hand wa11. of the air chamber 38, which is connected through the passage t? with the chamber 44. A compression spring t8 keeps the valve 32 in the open position shown. Chamber M communicates through the restricted passage t8 with the inlet manifold 5B. The tube i8 forms a central passage in a valve 58, which is ,the valve which' closes the entrance to a venturi 52. A spring 86 seats the valve 58 under normal conditions.

fold 58 whenever the car drives the engine, thatl is, during the deceleration period. This high suction moves the diaphragm 62 to the right. Parts 6E, 66, 68, 10, 12, '18, 'I5 8.116.778 all move to the right under -the influence of the movement of the diaphragm 62. Thereupon, the valve 16 closes the connection between passage 88 and passage 82. High suction is immediately developed in the chamber 48 from. the restricted passage 88, which is in communication with the inlet manifold 58.

The spring 86 is compressed as the valve 58 rises,

Restriction 84 connects the throat of the venl turi 52 with the passage 58, which communicates with the chamber 68, to the right of the diaphragm 62. The left-hand side of the diaphragm 82 is exposed to atmospheric pressure. A rod 65, a compression spring 66, a compression spring' adjustment 68 and a lever 18, connected to the rod Sli, operate through a pin 12, which pushes against a spring 14, which spring 14 moves a valve 16 and compresses a spring 18, so as to interrupt the connection between a passage 88 and a passage 82. This passage 88-82 connects the air entrance i8 with the chamber 4t. An

atmospheric pressure acting under the diaphragm 56.

Theflow of air through venturi 52 keeps the valve 16 closed long after the suction in manifold 58 has fallen below the suction at which the valve 58 opened. .If this valve 16 remains closed too long, then the engine will stall; hence, the adjustment 56 makes it possible to determine the critical value of the depression in 58 up to which value it is safe to keep the valve 58 open.

Stalling will result when the Vacuum in the inlet manifold 58 reaches 18 orll" Hg, for example. During the time that the valve 18 is closed, and during the time that the valve 58 is open, valve 32 is closed. This results from the fact that the pipe 42 applies the Venturi suction to the chamber 38 whenever the valve 16 is closed. The Venturi suction in the chamber 38 acting on the diaphragm 36, compresses the spring 88 and.

moves the valve 32 to the left. Atmospheric pressure acts on the tube 92 and is transmitted through the valve 32, which has a passage through it, to the chamber 38 to the right of the diaphragm 86.

Whatclaimis: i 1. In a carburetor for an internal combustion engine having an air entrancafan air passage,

a fuel supply means, a fuel nozzle connected therewith and discharging into the air passage, a throttle valve controlling the flow of mixture out of said passage, an additional air entrance on the `engine side of said throttle, a venturi in said additional air entrance, an air valve controlling the additional air entrance leadingv to said venturi, a' nioving wall mechanically connected to said valve, a chamber associated therewith, a passage connecting said chamber with the atmosphere, a control valve in said passage, a passage connecting said chamber with the' throat of said venturi so that the suction in said throat acts to open said air valve, a second chamber, a second moving wall forming a wall of said second chamber, a passage connecting the second chamber with said Venturi throat, a mechanical con` venturi.

, 4 turi first to the suction throttle for lrst moving said fuel valve into the closed position, and, when the air valve controlling the air entrance to said venturi is open, to

hold the fuel valve in its closed position during' period by the suction in said.

the deceleration ROBERT H. HIEGER.

REFERENCES ciTEn The following references are of record in the flle of this patent:

.UNITED STATES PATENTS Number Name 4 Date 1,176,627 Ver Planck Mar. 21, 1916 1,895,279 Constensoux Jan. 24, 1933 2,095,746 Jacobs Oct. 12, 1937 2,312,816v Heftler ,Mar.2,1943

1,067,502 Browne July 15, 1913 on the engine side of they 

